Challenges of Equipment Support in a Factory with a Diverse Multigenerational Toolset

Challenges of Equipment support in a factory with a diverse multigenerational toolset

David W. Brindza*, Travis A. Abshere

TriQuint Semiconductor, 2300 NE Brookwood Parkway, Hillsboro, OR 97124 [email protected] (503)-615-9625

Abstract: Doing business in a cost competitive Gotcha’s: These tools do not come without Market in a fabrication facility of limited size and challenges. First there is the issue of moving an budget requires that we continue to use some of existing process to a new platform. Since a new our process equipment far beyond a normally platform can have a different set of facilities inputs, accepted lifespan. This paper will cover many of the functionality, and wafer environment the process best known practices that have enabled success in a will probably, read this as almost never, transfer very diverse equipment environment. It will present exact. Many hours of engineering will be spent to an explanation of the major equipment groupings match critical output characteristics such as and the support challenge for each along with the deposition or etch rate. Matching device profiles practices put in place to accomplish high volume and required parametrics will often be frustrating. manufacturing requirements. As far as supporting from a maintenance standpoint this category of equipment provides logistical Process equipment can be divided into three challenges. major groupings, or generations: State of the Art, Tried and True Workhorse equipment, and Legacy Recommendations: For the first tool purchase, you equipment. Each of these groups presents a must address the logistics behind spare parts, different set of benefits and obstacles that need to develop a trained maintenance technician force , be addressed from both Process and Equipment and write all internal documentation/specifications perspectives. for the toolset before the tool goes into production. It is critical to take full advantage of the potential State of the Art equipment represents the benefits of vendor support on State of the Art tool latest technology in any given equipment set. This purchases. This is the best opportunity to specify equipment is generally considered to be the clear capability requirements, acceptance testing currently produced equipment by an OEM (original criteria, process development support, training, equipment manufacturer). maximum allowed response times for tool issues, and continued software upgrades. Benefits: State of the Art equipment usually comes with factory support for both process and The next category of equipment is the maintenance. Depending on the OEM there may be Workhorse toolset. We all have some of these. Even anything from onsite OJT (on the job training) to though the OEM has stopped production of the formal factory training for both process and particular model there are enough of them in use maintenance. These equipment sets will usually be that they have reached critical mass. Either the delivered with manuals that cover process setup OEM still supports the tools or there is enough and development, Maintenance basics along with profitability that independent companies have been recommended PM (preventive maintenance) cycles, formed around support of these tools. and an illustrated BOM (Bill of Materials). You may think, with all of this support behind the purchase Benefits: Anything from parts to software to both of a shiny new tool, this would be an easy selection, process and maintenance support can easily be but hold on. found. Some of this classification of equipment has even spawned a support base strong enough to develop new operating systems, rebuild tools, or refurbish the equipment with updated parts and company into continued support of Legacy electronics. Adding more tools into the facility from equipment if the shiny new equipment on the this category is less expensive, and usually has the market does not offer the same capability. Legacy benefit of an existing knowledge base internal for products that rely on the older equipment can do their support. If not, there is more opportunity for the same. The high support costs and potential for hiring in engineering support with previous extensive delays from difficult to replace experience on the toolset. Documentation may also components round out the down side for this already be in place along with an inventory of group. commonly used parts. Recommendations: Most OEMs will communicate Gotcha’s: A couple of challenges provided by the to all known customers before they discontinue continued use of this type of equipment is that the support for a toolset. The time to start a operating systems become trailing technology and communication effort with the OEM is as soon as training new employees in the support of these you receive that notice. Information to try to get tools becomes an internal responsibility. from the OEM before they totally abandon the tool can include build data for each of your tools, Recommendations: Stay ahead of obsolescence by production drawings for all parts, and any software working with the third party vendors to develop documentation available. It will probably take some modifications to operating systems and electronics convincing to get the OEM to release this type of to extend the life of these tools. Take advantage of documentation start as early as possible to convince the wealth of knowledge by joining or developing them to release it. user groups for these tools. One of the most critical assets in support of The third classification of equipment to any of these equipment groups is a strong discuss is true Legacy equipment. This is equipment, Equipment Engineering Group. These engineers not or subsystems of equipment, that has very little to only need to be experienced in hardware and no support outside of internal knowledge. maintenance but also in the process that the Supporting these tools is particularly difficult, equipment will be running. We all know that expensive and requires extra resources to maintain. compound semiconductor processing is vastly Generally these are systems that did not become different from an equipment capability standpoint mainstream tools throughout the industry, there than Silicon. These engineers will be constantly are not enough of them to spawn the secondary working to improve the handling and reliability of support market, and/or they were developed the toolsets they are responsible for. For the ideal internally. Tried and true workhorse equipment will EE group it is also invaluable to have a dedicated also end up in this category when the profitability Mechanical Design Engineer that can provide goes out of the secondary market. This category production drawings for reverse engineered parts equates to being on an Island where you need to be as well as design of new improved parts. The totally self sufficient. mechanical engineer will also be relied upon to work with machine shops and other raw material Benefits: Unlike a shipwrecked castaway, you know vendors in the manufacture of these parts. When you will be stranded so you have the opportunity to developing improved parts it is wise to make sure pack! Self sufficiency on a Legacy toolset should be you retain the rights to the drawings and even started long before getting stranded. If properly develop a controlled database of these internally. prepared, Legacy equipment can push out new Also insure that “non-disclosure” agreements are in capitol expenses and can sometimes even be place with all vendors and shops prior to sharing expanded for very little cost. any information. Gotcha’s: A real or even perceived technical Specific Examples: advantage from a Legacy toolset can force a Now I will focus on a tool from the truly logging and fault isolation that the state of the art legacy group that we have been supporting in our equipment has built in. Adding these capabilities factory for over 15 years and cover many of the has been possible but requires IT and IS support things we have done to keep it running. personnel. We have implemented systems that mimic secs/gem capabilities with recipe First is staying in contact with the original download/verification. These have reduced the engineers and support personnel that worked on incidents of wrong recipe selection due to human this tool from the beginning. The rolodex becomes error. Adding fault detection and data collection to your best friend. Be sure and stay in contact with some of these systems can be complex. It can span these people on a regular basis. They usually will from connecting interface equipment to existing have moved on to new jobs in different areas but sensors and electronics to building stand alone retain the knowledge and sometimes written sensor and wiring systems and building alarm information in the form of notes and logs. This is interfaces to create the equipment control loop. especially necessary when it comes to software. Fortunately there are vendors that specialize in When trying to maintain trailing technology such as helping to design and interface these systems. outdated operating systems (QNX2, DOS, Older versions of windows) it is great to be able to contact The bottom line is that no matter what you the person who wrote the drivers for the system. do you will eventually reach a point where it is no Building internal knowledge to cover this is very longer profitable to maintain the oldest of difficult. The best procedure to mitigate down time equipment. It is here that you need to develop a due to software or computer issues is to keep up to good exit strategy. Again, start as early as possible date clones of the hard drives or flash drives and to determine a new tool that will be able to run the backups of any configuration files. These are process. Remember, there will never be enough frequently used when tools are rebooted and files time when you are faced with factory output get corrupted or a hard drive crashes. As for requirements. hardware we have literally reverse engineered, redesigned, second sourced, or upgraded every part Conclusion: From state of the art to truly out of of the tool. Our database of equipment drawings date, supporting a diverse set of tools in same for this toolset has over 2000 manufacturing factory presents many challenges. Resource drawings. Building good relationships with vendors allocation is key in providing consistent productivity is key to getting them to work with you to from each toolset. Developing strong Equipment manufacture these parts. We have also dedicated Engineering group is critical to supporting the older, an equipment engineer and two senior equipment less supported equipment. The ability to be flexible technicians to full time support of this toolset. in all aspects of tool support provides the capability of success. In many cases equipment in the second and third categories do not have the capability for data